Glass melts are generally prepared from a mixture of raw materials, for example sand, limestone, soda ash, basalt, glass cutlet and other constituents melted in a melter at temperatures in the order of 1250 to 1500° C. The melt is subsequently submitted to a forming step for example for manufacture of flat glass, hollow glass, continuous fibers for reinforcement purposes or fibers for insulation purposes; a melt refining step may be required upstream of the forming process. The chemical composition of the melt and its physical properties are selected as a function of the intended use and the forming process.
In the manufacturing of mineral wool insulation products, a certain amount of waste material is produced, for example from trimming manufactured products to desired dimension. The presence of organic material on the fibers, for example binder or resin, renders the recycling of such waste material in the manufacturing process difficult. In addition, increasing use of mineral wool insulation materials in the construction industry also leads to increasing quantities of waste insulation material being generated in case of destruction or refurbishing.